Multi-sided shafts are commonly used for power transmission applications for which round, keyed shafts provide inadequate power transmission capabilities. Sometimes, apparatus such as and overrunning clutch will be utilized with a multi-sided shaft to avoid shaft breakage and other problems which can occur, for instance, when overpowered, or movement of the driven portion of the apparatus is prevented, or reduced relative to the driving element. A representative application is an agricultural combine harvester wherein power is to be transferred from the engine of the harvester to a large power consuming subsystem or subsystems, such as conveyors, and/or the header and infeed subsystems.
A variety of releasable, tapered locking hub constructions are known. Reference in this regard Firth U.S. Pat. Nos. 2,402,743 issued Jun. 25, 1946; 2,519,958 issued Aug. 22, 1950; and 2,763,158 issued Sep. 18, 1956. These known locking hubs generally include a split inner hub having a round bore therethrough that fits around a round shaft, and a tapered outer surface. The locking hubs also have an outer hub having a tapered inner surface defining a center bore that receives the inner hub, such that the tapered inner and outer surfaces can be matingly engaged, to compress the inner hub around the shaft for holding the locking hub in position on the shaft. The outer and inner hubs also include half-holes or bores at spaced locations around the tapered inner and outer surfaces, outer sides of some of the bores being threaded so as to be threadedly engageable by a screw inserted in the bore for moving the inner and outer hubs into engagement, and inner sides of others of the bores being threaded for jacking the outer and inner hubs apart. This has been found to be a useful feature, and would be desirable for use with higher power transmitting applications, such as multi-sided shafts used in the above applications.
Accordingly, what is sought is a releasable locking hub configuration adaptable for use with multi-sided shafts, and power transmission levels typically transmitted thereby.